Oskarsson Sven, Dawes Christopher, Johannesson Magnus, Magnusson Patrik K E
Department of Government, Uppsala University, Uppsala, Sweden.
Twin Res Hum Genet. 2012 Feb;15(1):21-33. doi: 10.1375/twin.15.1.21.
Recent studies have shown that trusting attitudes and behavior are biologically influenced. Focusing on the classic trust game, it has been demonstrated that oxytocin increases trust and that humans are endowed with genetic variation that influences their behavior in the game. Moreover, several studies have shown that a large share of the variation in survey responses to trust items is accounted for by an additive genetic component. Against this backdrop, this article makes two important contributions. First, utilizing a unique sample of more than 2,000 complete Swedish twin pairs, we provide further evidence of the heritability of social trust. Our estimates of the additive genetic component in social trust were consistent across the sexes -- .33 for males and .39 for females -- and are similar to the results reported in earlier studies. Secondly, we show that social trust is phenotypically related to three psychological traits -- extraversion, personal control, and intelligence - and that genetic factors account for most of these correlations. Jointly, these psychological factors share around 30% of the genetic influence on social trust both for males and females. Future studies should further explore the possible causal pathways between genes and trust using panel data on both psychological traits and social trust.
近期研究表明，信任态度和行为受到生物学影响。聚焦经典信任博弈，已有研究证明，催产素会增强信任，而且人类具有影响其在该博弈中行为的基因变异。此外，多项研究表明，调查中对信任相关问题回答的差异很大一部分可由加性遗传成分来解释。在此背景下，本文做出了两项重要贡献。其一，利用一个包含2000多对完整瑞典双胞胎的独特样本，我们进一步证明了社会信任的遗传性。我们对社会信任中加性遗传成分的估计在两性间是一致的——男性为0.33，女性为0.39——且与早期研究报告的结果相似。其二，我们表明社会信任在表型上与三种心理特质——外向性、个人控制感和智力——相关，并且基因因素在这些相关性中占主导。总体而言，这些心理因素对男性和女性社会信任的遗传影响均约占30%。未来研究应利用关于心理特质和社会信任的面板数据，进一步探索基因与信任之间可能的因果路径。
